Edward martin knight



E. M. KNIGHT.

mm. APPLICATION FILED DEC. 2. 1918.

1,818,388. Patented Oct. 14,1919.

[17m n 1. mar/77 EDWARD MARTIN" KNIGHT, OF OTTAWA, ONTARIO, CANADA.

- FILTER.

Specification of Letters Patent.

Patented Oct. 14, 1919.

Application filed December 2, 1918. Serial No. 265,029.

To all whom it may concern:

Be it known that I, EDWARD MARTIN KNIGHT, a citizen of the United States, and residing at 344: Itlverda'le Ave, in the city of Ottawa, Province of Ontario, Dominion of Canada, have invented certain new and useful. Improvements in Filters, of which the following is a specification.

This invention relates to filters and applies in particular to that class of filters that employ an asbestos cloth with carbon spread on it, and has for its objects:

(a) To facilitate the application of the carbon. 7

(b) To prevent the closing up of the pores of the asbestos cloth or other material used as a supporting means for the carbon.

(0) To facilitate the removal of the old, used carbon bed and its renewal.

(d) To obviate incurring of the mess and trouble hitherto accompanying both the application and removal of the carbon.

(6) To provide means for independently affixing and supporting, (1) the asbestos supporting cloth, (2) the carbon bed.

In the old and well known form of perpendicular frames using asbestos sheets with carbon in the form of paste as a filtering medium, it has been found extremely difficult to form an even layer of carbon on the supporting asbestos sheet, and to sustain it there when water was admitted to the vessel containing the frame, and when the carbon got thoroughly permeated with impurities extracted from the water, and hence it was necessary to remove and renew the same whereupon the diificulties were encountered again. Moreover by the repeated applica tion of carbon (in the form of paste) the tendency was to choke up the pores of the asbestos cloth itself, thereby obstructing the fiow of purified water, having a tendency to permanently contaminate the asbestos cloth itself, thereby nullifying the purifying effects of the carbon bed. Now it has been the object of the present invention to devise means by which these serious defects manifested in the old construction of this class of filter, and the means taken to do so are essentially as follows:

Instead of permanently attaching the asbestos cloth to the frame by means of soldering it the cloth is attached to the body of the frame by a separate ring or frame which by being pressed over the edges of the cloth confine it tightly to the body of the frame. By this means the cloth can at any time be removed and renewed if necessary.

The carbon bed isapplied as follows:

Instead of applying the carbon direct to the cloth it is confined between two sheets of fibrous material, preferably of prepared paper. This film or diaphragm is then placed over the asbestos cloth and forced in close contact with-it and held in position by a separate ring similar to the one confining the cloth to the frame. By this means the previous defects are obviated and the following advantages obtained:

1. When the water is supplied to the containing case the bed of carbon is protected from being disturbed.

. 2. The water passed freely through the carbon without being forced in anyway into the supporting cloth.

3. VVhenthe carbon becomes choked with impurities and requires renewal, the ring confining the film or diaphragm is removed I and the-old film taken out'and thenew one replacing it inserted.

There is another advantage that these films have over the old method; the carbon bed when applied directly to the cloth was of such delicate nature that the slightest vibration disturbed it and its efficiency was impaired. But when these films are used this is entirely obviated.

These films can be very inexpensively produced and by their use save the considerable waste that is incurred under the old system.

In the drawings:

Figure 1 is a sectional elevation of the embodiment of the invention.

Fig. 2 is a sectional detail through the filtering drum.

Fig. 3 is a detail of one of the filters of the carbon beds.

Fig. 4 is a section through the carbon bed.

Fig. 5 is a sectional detail through the rings which hold the bed in position.

In the drawings like characters of ref erence indicate corresponding parts in all figures.

For the sake of illustration I have shown the present invention applied to a special type of drum filter. It is to be understood that the structure of the filter apart from level within the container by means of a float valve 12, a deflecting plate 13 being provided below the outlet of the valve. B represents the filter drum located within the container A cylindrical in form having the filtering material stretched over its open ends.

Extending inwardly from the end of the drum are conical members 14: and 15 which may if desired form supports for additional filtering elements.

An outlet conduit 16 with suitable per forations for the inlet of water leads from the drum. The filtering faces on the drum are constituted in the first place by a sheet of asbestos cloth C, held in position by means of a ring 20 which holds the same against the periphery of the drum.

D represents the carbon filtering element which in accordance with this invention consists of a quantity of finely divided carbon confined between two sheets or disks 21 and 22 of fibrous filtering material, such as filter paper, the edges of which are fastened together by glue or other suitable means. The edges of the carbon filtering element are held in position by means of a clamping ring 23, which clamps the turned edges against the ring 20, the ring 23 being formed with an inwardly turned flange 24 which fits over the edge of the drum.

As previously explained the carbon filtering element may be removed separately from the asbestos elements and the further advantages already explained will be obtained by their use. I

As many changes could be made in the above construction and many apparently widely different embodiments of my invention within the scope of the claims constructed without departing from the, spirit or scope thereof, it is intended that all matter contained in the accompanying specification and drawings shall be interpreted as illustrative and not in a limiting sense.

What I claim as new is:

In a filter in combination, a filter member having an opening through which the water being filtered is adapted to pass a sheet of asbestos cloth covering the opening to said member, a ring adapted to hold the edge of said asbestos sheet against the member, a carbon filtering element, a ring adapted to hold the edges of the carbon filtering elements against the first mentioned. ring, whereby the carbon filtering element may be removed separately and independently of the asbestos sheet.

.In witness whereof I have hereunto set my hand.

EDWARD MARTIN KNIGHT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner 'ofjIEatents,

Washington, 1L0. 

